Each brick contains a powerful LED. You can use them to build imaginative light creations and you can also use them to light up your own collection of building blocks. What is a house without lights, a car not able to blink or a lighthouse with … well just dark bricks? LIGHT STAX comes in a wide range of both solid and transparent colors. They work with and without wires, have multiple lighting modes, and a sound activation mode so the bricks light up in response to sounds or music. LIGHT STAX are compatible with LEGOs.